How would you convert Sodium Sulfite into......

[yvonbug]

How can I convert the Sodium Sulfite that I have 5 lbs. of, into Sodium Metabi-sulfite? I think this would solve a problem I'm haveing.

 

[goldsilverpro]

I used sodium sulfite to drop gold daily for about 20 years. Why do you think this is why you're having problems? What exactly, are the problems you are having. Can you detail your process? Usually, when one of the sulfites doesn't drop the gold, it is caused by free nitric remaining in the aqua regia. Either that or there's no gold in the solution.

 

[Platdigger]

I think the only thing about "Sodium Metabi-sulfite" is that it is easier to come by for most. Nothing more. If I could have found sodium sulfite just as easiy and cheaply, I would have probably purchased that instead.

 

[yvonbug]

Well, I've been useing SS for years now, also. I took a short vacation from it, (refining) and now I'm back into it. But, I got in a rush, and skipped the nitric digest part, put the pretty little pins straight into AR, filtered it once thru coffee filters and then proceeded to be stupid and drop it out just like that. I deserve to have nothing drop out, don't I? -Y- soooooo, Now that I've tried to drop it out like that, and not much happened, what shall I do to fix it? I love this place!

 

[Harold_V]

I got in a rush, and skipped the nitric digest part, put the pretty little pins straight into AR, filtered it once thru coffee filters and then proceeded to be stupid and drop it out just like that. I deserve to have nothing drop out, don't I?

The important consideration is if you learned anything.

Two things should come to mind.

(1) Don't dissolve anything with AR that can be processed first with other acids to eliminate base metals, or can be stripped by other means. Remember---garbage in-----garbage out. If you expect your precious metal to come out pure, you have to eliminate the base metals at some point.

(2) Don't attempt to precipitate without eliminating nitric, assuming you've used it in the process. I never used urea, always evaporated. Can't comment on urea, but evaporation isn't a big deal, especially if you use a button of gold to help consume the nitric.

soooooo, Now that I've tried to drop it out like that, and not much happened, what shall I do to fix it?

Start by determining where the gold is. If you had any pins left, it's entirely possible your gold isn't in solution, but left behind as mud in the filter and container you used for the process.

Assuming it is in solution, and that you had totally digested the pins, you have two options. Evaporate to eliminate the nitric, or recover everything in solution, using scrap steel, then start over, eliminating the base metals before dissolving the gold.

Your move. (We're getting close to check-mate).

Harold

edit: added two words to correct typo.

 

[NobleMetalsRecovery]

Ha Ha, I like the checkmate part.

When using iron to solve a problem, and after all the metals have dropped, can you now just use nitric to remove the base metals?

You mention using a gold button to help get rid of the nitric acid. I guess the point is that the unused AR will attack the gold, thereby consuming the nitric acid?

Do you do the standard 3 evaporations?

 

[Harold_V]

When using iron to solve a problem, and after all the metals have dropped, can you now just use nitric to remove the base metals?

Yes, you can, and that's the recommended procedure, but you have to be wise about how you go about the process. In place of scrap steel, you can also use zinc, assuming you have it at your disposal. No need to get any if not. I'd also like to mention that this should not, in any way, be construed as a replacement for dissolving the values in AR, then precipitating them for final separation. It is a necessary step prior to that operation, to get rid of unwanted metals.

If, by chance, you intend to pursue this process, it might be wise for you to contact me on the side for a few pointers. It's dead easy, but you should do things in logical order in order to not further complicate the process.

Back to the material in question, if you have traces of chlorides present, it's possible to dissolve some of the values, so you don't get far ahead. If you have a lot of base metal, and you've fairly well dried the material prior to using nitric, you should be fine. To insure that you are, I had a tendency to incinerate everything between changes in acids if there was any chance of losing anything to early dissolution. That may or may not be an important step, depending on existing conditions.

I mention this for good reason. When you don't use primary processes, you included a lot of garbage in your AR solution that can be troublesome. I'm not implying that that is your fate, but lets assume, for purpose of discussion (and your education), that the material you've recovered, or are in process of refining, is contaminated in that fashion, and will yield a solution that will be difficult, if not impossible, to filter prior to precipitation. Here's what I used to do, a process that was never found in print, but provided a much needed addition to the procedure.

After the nitric digest, in which you'd have removed the majority of base metals, I would then incinerate the remains, after getting everything in a Sharkskin filter. They're tough and fairly open, so allow rapid filtration. I would then incinerate the entire lot, which, by now, is generally not much material. Once incinerated, I'd do a wash with HCL acid, which would dissolve the balance of substances that were troublesome, then follow up with a tap water wash. I would then dissolve the remains in AR, yielding a solution that was very clean, and easily filtered. The quality of gold from an operation such as this can be very good----especially if you use good gold washing techniques after precipitation.

You mention using a gold button to help get rid of the nitric acid. I guess the point is that the unused AR will attack the gold, thereby consuming the nitric acid?

That's correct. It was a procedure I employed routinely. In order to know what gold belonged where, I weighed the button prior to introducing it to the lot, then weighed it afterwards. That way you know how much gold you added to the process, in case the material in question is not yours, or you're trying to determine a yield of a given batch. It is important that you add additional HCL to this process, to insure that the nitric acid is consumed. You can tell by the reaction if it has been or not. If not, you'd see action at the button.

Do you do the standard 3 evaporations?

That's an interesting question. As much as I've read about refining, nowhere have I read that there must be 3 evaporations, and my experience dictates that's nonsense. One proper evaporation is more than adequate. It should consist of introducing a few drops of H2SO4, which will expel any unwanted lead as lead sulfate, which will then be filtered from the gold solution upon final filtration, then evaporating until the solution changes color and is well condensed. Additional HCL would be added at this stage, which helps expel the nitric. If you work with relatively clean solutions, they turn from golden colored to deep red, then lean towards a blackened red color. Dirty solutions are affected by the contamination, but tend towards black, or even dark green. It's not quite as easy to know when you've finished with the evaporation process when you're working with dirty solutions, and they have a tendency to bake out on the evaporating dish if you go too far. You have to use care when evaporating towards dryness, for it happens quickly. Once evaporated, it stands to reason that you would add water (tap water is fine unless it's very heavily contaminated with metals) to the evaporated gold to your satisfaction. I kept mine fairly concentrated to keep beaker size small. That isn't necessary, it just worked better for processing large amounts of gold in small vessels. I added ice to the solution prior to precipitation, which kept the solution from over heating. Precipitation is an exothermic reaction, and will heat the solution to the point where it won't precipitate well when the concentration is high enough. Mine generally was, especially when re-refining.

As a side note, if you've read any of my posts, you're likely tired of hearing me constantly harp on Hoke's book. If you don't have it, buy it! Not tomorrow, not next week, and not when you feel it might be convenient. Buy it NOW. You should look upon that book, or one its equal, as being just as important as having a tank of fuel in your automobile when you anticipate a trip. Without it, there are simply too many unknowns that will haunt you no end.

Almost everything I learned about gold refining came from that book, and it carried me through more than 20 years of refining. I recommend it highly---------and ----no------I am not connected with the book in any way aside from knowing it's the best text out there for a novice. It's written in plain English, with no nonsense instructions aside from her constant recommendation to use gasoline when incinerating. I hope you understand that's totally insane!

Hope this helps. I'm open to further questioning, assuming I've left you with more questions than answers.

Harold

Edit: corrected typo, and added new comments.

 

[NobleMetalsRecovery]

Hi Harold,

Thanks for the detailed reply. I just did a quick read of it and will return to fully digest it later to eventually precipitate the nuggets it contains. At first glance it all makes good sense and is easy to follow. Much appreciated. That's good news that one evaporation can do the trick. Ammen preaches 3 evaporations, so do some others, I'll let you know when I can think of them.

Regarding the Hoke book, I have studied the Ammen book these past 15 years and have only recently been paying careful attention to Hokes book that I've had for several years. The copy I have happens to be a first edition, hardback, with the gilt cover. (It's probably for sale, like most everything else I have at the moment, but I would need to get a reprint edition in trade).

My library on this subject consists of around 50 different titles or so, spanning a period of 100 years.

Are you aware of the book by Gee written in the early 1920's, I see traces of that book in Hokes book, and traces of Hoke's book in Ammens book.

Over and out for the night.

Steve

 

[dsinjc]

tried to send this harold , but for some reason the pm would not go
feeling really stupid


after i read your replies i decided to do alot more reading it seems that i jumped the gun. I mixed up a batch of AR and put some pins that i have in them ( i believe you saw the pics of the pins i had up in a question a few weeks ago when i arrived here ) and yes you were right the platinf was over copper !!!!
So i mixed up the solution and dropped in the large pins ( 1/4 in. in diameter by 3 inches long. the solution started to fizz then got very dark and hot !!
i tried to watch the reaction closley and remove the pins as soon as the plating was off as not to contaminate the solution to much.then i was left with a very dark solution unable to see through with a flashlight !
used urea to neutralize , and used sodium bisfulate( which i learned later was wrong ) first off when adding the urea i got no fizzing as is explained here alot.
what i have is abaout a 1/3 of a gallon of solution that is black there is alot of what looks like gold flake on the bottom of the container.
and the solution itself looks saturated with shiny metalic particles.
have i totally screwed the proccess up?? , If so is there any fixing it ?? should i have used nitric first with these large pins,i have even larger ones aswell almost 1/2 inch in diameter x 3-4 inches long.
i feel kind of stupid i thought i read enough to start , but maybe not.

 

[yvonbug]

I really enjoy reading Harolds replies. So informative! (unfortunately, I don't play chess much) Sometime soon I'd like You (Harold) to put in print your incenerating-cleaning process. To the smallest detail. I know YOU can be a real benifit to me. Right now I've been sidetracked by the sudden death of my bosses 17ft. python. I'm in the process of skinning it, and it's taking up all my time right now. But I'll be back and let you know how I did my clean-up and how it came out. Hopefully real soon. -Y- PS Teach me more!

 

[Harold_V]

Sometime soon I'd like You (Harold) to put in print your incenerating-cleaning process. To the smallest detail.

It might be helpful for me to know what you process. My background consisted primarily of refining for the jewelry industry, with only brief excursions in the scrap electronics field. That's not to say that I don't understand how to refine the metal that is recovered, for I do. The problem is, there are systems that have been developed for use in recovering from such low grade wastes (electronic scrap sucks where precious metal content is concerned, but it is a reliable source, and readily available for those with an interest). How the values are extracted could very well dictate how I commented, and some of my comments are sure to rile a few that are not prone to being corrected, or don't care about the less than acceptable quality they produce.

I know YOU can be a real benifit to me.

Thank you for your confidence in my ability to assist.

Yes, it's true, I can be quite helpful, but I'm also somewhat narrow of mind where refining is concerned. I try to not allow others to muddy the water for me. Here's the reason.

There are many ways one can approach refining----all with varying degrees of complexity and results. One of the problems that occur is that an individual will seek advice from more than one source, then pick from the choices presented that which appeals to them most, often by combining methods from two or more sources. The problem comes when some of the processes are not compatible, so proper results are not achieved. Then the questions begin-----and known processes that should work without fail have not. I'm not properly informed of what has transpired. I can't assist because I have no clue what has been done, or why. In your favor, as long as you don't discard any of your materials, it's virtually impossible to tie up the values such that they can't be recovered.

Right now I've been sidetracked by the sudden death of my bosses 17ft. python. I'm in the process of skinning it, and it's taking up all my time right now.

Damned shame! I like critters. Any chance we could see a picture of the beast? They're a beautiful snake.

But I'll be back and let you know how I did my clean-up and how it came out. Hopefully real soon.

I'll keep watch, as will others. Luck!

Harold

 

[yvonbug]

Her name was Abby, in these pics she's pregnant. I've got one of her babies, his name is Howie, he's the little guy, last pic. I take care of 32 large reptiles.

 

[yvonbug]

Uh, Howies pic is the first one.

 

[Harold_V]

Her name was Abby, in these pics she's pregnant. I've got one of her babies, his name is Howie, he's the little guy, last pic. I take care of 32 large reptiles.

Wow! Beautiful beyond my expectations, and Howie, a plus for us, is a dandy.

My wife and I each enjoy critters, even snakes. We'd like to thank you for posting the pics, which we enjoyed very much. Susan took a break from making an apple pie to take a look.

Sounds like you have your hands more than full, yvonbug! Keep up the good work.

If I can be of assistance in your refining quest, don't hesitate to ask.

Harold

 

[EVO-AU]

Steve: I sure would like to get loose in your library. Browsing thru the forum I have this question for you. Have you ever read "De RE Mettallica ?" The woodcuts alone are worth a bunch. Phill